In fabricating disk drives, such as energy assisted magnetic recording (EAMR) disk drives, it may be necessary to bond components together. For example, in conventional EAMR disk drives, a laser provides energy used to heat the media for magnetic recording. The laser typically takes the form of a laser diode and is attached to a semiconductor submount, such as a Si wafer. The laser diode may be desired to be aligned with a waveguide on the slider and bonded with the slider.
FIG. 1 depicts a conventional method 10 for bonding two substrates, such as a conventional laser diode (or substrate on which the laser diode resides) and a slider. FIG. 2 depicts a conventional EAMR head 50 during fabrication using the conventional method 10. FIG. 2 depicts the conventional submount assembly 60 and the slider 70. The conventional submount assembly 60 includes a submount 62 and a laser diode 64. The laser diode includes an emission exit 66 from which the laser 66 provides a pulse during operation of the conventional EAMR head 50. The slider 70 includes a transducer 72. The transducer includes a waveguide 74 having an entrance 76. The transducer 72 may also include a read sensor 78 as well as other components used in writing to a medium (not shown).
The submount assembly 60 is aligned to the slider 70, via step 12. More specifically, the emission exit 66 is aligned with the entrance 76 to the waveguide 74. This is typically done using alignment marks (not shown) on the slider 70 and submount assembly 60. The submount assembly 60 is attached to the slider 70.
Although the conventional method 10 may function, the method 10 may be problematic. Portions of the slider 70 may not be heated to above 200 degrees centigrade. For example, the ABS, particularly the read sensor 78, may be damaged by temperatures in excess of 200° C. If solder is used, many solders, including Sn, melt at 230° C. If the slider 70 is heated sufficiently to reflow such solder, then the transducer 72 may be damaged. The conventional EAMR head 50 may thus not function as desired. In addition, cooling during after heating may affect the alignment between the slider 70 and the submount assembly 60. This may adversely affect yield. In order to avoid such issues, glue or epoxy may be used. However, many epoxies are cured at high temperatures, which may result in the same issues as for solder. If glue is used instead, the joint between the submount assembly 60 and the slider may have poor thermal conductivity. In addition, the joint may be mechanically unstable.
Accordingly, what is needed are improved methods and systems for attaching the submount assembly including the laser diode to the slider of an EAMR disk drive.